1. Field of the Invention
The present invention relates to a switchable two dimensional/three dimensional display (2D/3D display), and more particularly to a switchable 2D/3D display equipped with a switchable barrier.
2. Description of Related Art
In recent years, continuous advancement of display technologies results in increasing demands on display quality of displays, such as image resolution, color saturation, and so on. Nevertheless, in process of purchasing a display, whether the display is able to display 3D images or not is also taken into consideration in addition to high image resolution and high color saturation.
In current 3D image display technologies, a fixed barrier is mainly utilized for controlling images captured in respective eyes of a viewer. However, according to visual characteristics of human eyes, a 3D image may be produced when two images with the same content but different parallax are respectively captured by a viewer's left and right eyes. Based on different positions of the fixed barrier, the 3D image display technologies can be approximately categorized into a front barrier 3D image display technology and a back barrier 3D image display technology.
In the front barrier 3D image display technology, the barrier is disposed in front of a display panel, i.e., the barrier is located between the display panel and human eyes. By contrast, in the back barrier 3D image display technology, the barrier is disposed between a backlight source and the display panel. The front barrier 3D image display technology is further detailed in US publication number 2004/0257531, while the back barrier 3D image display technology is described in US publication number 2007/0229654 A1.
It should be noted that a 3D image is produced by means of the fixed barrier in a spatial-multiplexed manner, whereby the resolution of a 3D display device is reduced in half even though a 3D display effect of a liquid crystal display (LCD) panel can be achieved. Besides, the 3D display equipped with the fixed barrier cannot be used to display 2D images but 3D images. Thus, the 3D display having the fixed barrier cannot be extensively applied.
To resolve said issue, a switchable barrier has been proposed and applied in a switchable 2D/3D display such that the switchable 2D/3D display is able to display 2D images when the switchable barrier is turned off. By contrast, when the switchable barrier is turned on, the switchable 2D/3D display is able to display 3D images.
FIG. 1 is a schematic cross-sectional view of a conventional switchable 2D/3D display. Referring to FIG. 1, a conventional switchable 2D/3D display 100 includes an LCD panel 110 and a switchable barrier 120. The LCD panel 110 has a display area 110a, a non-display area 110b surrounding the display area 110a, and a first black matrix 112 extending from the display area 110a to the non-display area 110b. The first black matrix 112 has a plurality of openings 112a arranged in array and merely distributed within the display area 110a. The switchable barrier 120 has a 3D image control area 120a, a non-display area 120b surrounding the 3D image control area 120a, and a second black matrix 122 merely disposed within the non-display area 120b. The second black matrix 122 surrounds the 3D image control area 120a, and an area occupied by the 3D image control area 120a is the same as an area occupied by the display area 110a. In other words, the area of the non-display area 120b is the same as the area of the non-display area 110b. 
It can be deduced from FIG. 1 that an outer edge of the 3D image control area 120a is aligned to an outer edge of the display area 110a. Hence, when the conventional switchable 2D/3D display 100 is used, it is rather perceivable that the images do not present a favorable visual effect on the edges of the images. In particular, the second black matrix 122 is not likely to completely block the viewer from visually perceiving the first black matrix 112 located on the edges of the images.